There are alternatives to chlorine for disinfecting water during vegetable processing. This was the conclusion of the PhD thesis Battling microbes: disinfecting water during fresh-cut lettuce processing by Jen Banach. She will be awarded her PhD for her research on this topic at Wageningen University on Friday 9 April.
Little research alternatives
Worldwide, chlorine is often used to disinfect the water during vegetable processing. Due to potential safety concerns, some European countries are looking for alternatives to chlorine, but this has been difficult because little research has been conducted on other agents.
This was a reason for Banach to devote her PhD research to this topic. She investigated the impact of alternative chemical water disinfection techniques when washing fresh-cut lettuce.
Reducing the action of harmful bacteria
Her research showed that washing lettuce in water disinfected with agents such as chlorine dioxide and peracetic acid reduced the action of harmful bacteria. The efficacy of disinfectants depends on aspects such as the dose, the organic load and the temperature of the water.
Besides conducting laboratory analyses and pilot projects, Banach also studied the effects of these alternative disinfectants from a broader perspective. She looked not only at the efficacy of the disinfectant, but also at other issues such as technological and economic aspects, consumer acceptance and health.
Ultimately, peracetic acid turned out to be an alternative with the right balance between safety and efficacy when used for disinfecting water while washing fresh-cut lettuce.